Josiah fowler



(No Model.)

J- EOWLER.

MACHINE FOR BBNDING SPRINGS.

Patented May 1,1883. Imam! John, in the county of St. John and Province surface.

side with a raised ledge or flange, a, to facilijected on the upper side to a pressure at the UNITED STATES PATENT OEEIcE.

JOSIAH FOWLER, on sr. JOHN, NEW BRUNSWICK, CANADA.

MACHINE FOR BENDING SPRINGS.

SPECIFICATION forming part of Letters Patent No. 276,678, dated May 1, 1883.

Application filed March 31, 1882. (No model.) Patented in Canada, November 22, 1892, No. 15,836.

To all whom it may coiwer n Be it known that I, JOSIAH FOWLER, of St.

of New Brunswick, Canada, have invented certain Improvements in Machines for Bending Springs, of which the following is a specificatron.

- My invention relates to the means for manufacturing those springs which consist of a series of superposed se mi elliptical leaves or spring-plates.

The invention consists in the machine for bending the plates consisting in the screwpress provided with concave and convex dies, the convex die being of greater width than the other, whereby the plates are supported across the entire face upon the under side, but subeenter only.

Referring to the accompanying drawings, Figure 1 represents a side elevation of my bending machine or press with the leaves in position therein to be acted upon. Fig. 2 is a detailed view, showing the manner in which the bending operation is performed and the action of the leaves upon each other during said operation. Fig. 3 is a cross-section of the same on the line as m. Fig. 4 is a cross-section on an enlarged scale, showing the form of the leaves previous to the application of pressure thereto.

Referring to the drawings, A represents a strong upright frame, which may be of any suitable construction, and which is provided at the base with a rigid convex die or anvil, B, having its upper surface given a longitudinal curvature corresponding with that required on the inside of the springs to be produced. This anvil is made of a width as great or greater than that of the spring, so as to give support to the bottom leaf throughout its entire under The anvil is also provided on one tate the adjustment of the blanks or leaves thereon. It is further provided at the center with the raised punch or protuberance b, for the purpose of keeping the plates in position. This protuberance may be simply employed to enter a previously-formed indentation in the bottom plate, or may be used to form the indentation in the act of bending the springs.

As shown in the drawings, each plate of the series will have an indentation on the under side and a corresponding elevation on the upper side, whereby they are retained in place one upon another.

In the upper part of the frame, immediately over the anvil B, I mount a vertical screw, 0, and upon the lower end of this screw I swivel a die or former, D, having its under side made concave with a curvature corresponding with that required on the outer side of the spring. The die is made of about the same length as the anvil B, but of a width on the face less than that of the anvil or of the spring blanks or leaves, in order that it may act only in a longitudinal line in the center or middle of the plates.

It w'illbe observed that the two dies are of dili'erent curvatures on their faces, in order that they may embrace closely between them springs having a greater thickness at the center than at the ends. By means of the screw the die D may be carried down upon the anvil B quickly and with great force.

I find in practice that it is highly essential to the successful carrying out of my invention that the upper die or former shall be carried downward very quickly and very forcibly, and that it shall be held in such manner as to prevent the slightest reaction or rebound, and, after using weights, cams, and other devices, I have found that the screw is peculiarly fitted for this purpose, and that when used in operating upon the spring plates or blanks its action difl'ers materially from that of the other depressing devices named. In other words, I find that the screw gives to the dies a peculiar operation and effect not otherwise attainable. The die or former D is provided in its under side with a central recess or cavity, 0, corresponding in location with the protuberance b on the anvil, so as to admit the protuberance which will be formed upon the top leaf of the series.

In proceeding to manufacture a spring I provide a suitable number of fiat blanks or leaves, E, of different lengths, as usual, arranging them in proper position one upon anoth.er,with

thus arranged is then placed upon the anvil B, as shown in Fig. 1, and after being carefully adjusted in position the screw 0 is turned at a sufficiently high speed to bring the die or former D down very quickly and forcibly upon the blanks, thereby bendingthem to the required form and clamping them firmly upon each other between the two dies, the blanks receiving a quick, dead blow, and being retained solidly in place, whereby they are given the permanent set or curvature required.

It will be observed that during the descent of the die or former D it first acts upon the i outer ends of the long blank and then successively and quickly upon the ends of the shorter blanks.

It will be observed that, as before noted, the

, successive blanks serve as formers or anvils for each other during the bending operation. This has been found in practice a matter of great importance and advantage, not only in that it permits the bending of the entire series of leaves at once, but in that as the leaves are bent upon and adapted to the surfaces upon which they are to remain permanently, a much closer, better, and more accurate fitting of the parts is secured than was otherwise attainable. When the plates or leaves formed 3. The leaves thus formed possess much greater strength and stiffness in proportion to their weight than those made of flat form, and owin g to their curvature they retain their position much more securely upon one another when in use.

The present invention is restricted to those matters and things which are specifically claimed herein, and asto all features which may be described and shown, but which are not claimed, the right is reserved to make'the same the subject of separate patents.

Having thus described my invention, what I claimis In a spring-bending machine, the combination of the curved broad-faced anvil B, guard a, narrow die D, and screw 0, as shown.

JOSIAH FOWLER.

Witnesses:

W. WATSON ALLEN, DANIEL MCINTYRE. 

